This is nearly full-frame, cropped to 8.10 aspect for compositional purposes. Shot with the Sigma 105 along with 3 Kenko tubes' worth of extension. These are tough to hand-hold; you're lucky if you get one sharp shot before the model has a fit and flies off to find a quieter spot.
It was lit with the single SB-800 shot thru a Lumiquest mini-lightbox, with the flash and difuser mounted on a CR flash bracket, and SC-17 cord provided a dedicated link.
I always shoot these at f16, 'cause diffusion kills the quality at f18 and beyond. It's funny; in the film world, I always thought the diffusion talk was just theoretical--the stuff of bar charts. With digital, lens quality is so much more apparent--just zoom to 100 percent, and there's your answer.
Thanks for looking,
Eric